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Footings and stem walls

I have poured a concrete wall monolithically with a footing. I am also aware that projects designed by other engineers are poured monolithically. I have inspected a number of these projects. California contractors are not dumb.

Keys are used to help transfer forces. keys are not needed in order to use bentonite.
 
I have poured a concrete wall monolithically with a footing. I am also aware that projects designed by other engineers are poured monolithically. I have inspected a number of these projects. California contractors are not dumb.

Keys are used to help transfer forces. keys are not needed in order to use bentonite.
It must be a regional thing in that case because I've never seen a footing in stem wall poured monolithically in either South Carolina or Kentucky. That applies to both residential, commercial and industrial buildings.
 
If California contractors can do it why cannot contractors in South Carolina?
 
It can be done anywhere in the country. It just may not be the fasted and most economical way to do it. I assume you do not deal with cold weather concrete and the extra expenses incurred when pouring concrete in cold weather.
 
It would seem the monolithic pour only works with formed footings, not with trench footings?

Any practical limit to height of wall poured with footing? It would seem the hydrostatic pressure of a tall wall might make it not worth it.
 
The secret is that you first pour the footing portion and then proceed to place concrete in the wall in relatively small layers. This works because the footing concrete has taken an initial set before the wall is poured. This is not a problem with stem walls of moderate to small heights.
Subsequent pours should be placed when the vibrators are still able to integrate the pour with the previous lift.

Low slump concrete does not hurt and is desirable for many reasons.

If by trench footings you are referring to concrete poured in a soil trench where the slab on grade is cast right over the footing, it is similar. First you pour and consolidate the concrete in the trench and then you start placing the slab on grade. It is done all the time.

In cold whether I would expect them to prefer high early strength concrete. Pouring small pieces of concrete will be more sensitive to freezing temperatures thus pouring more concrete at one time should help..
 
If by trench footings you are referring to concrete poured in a soil trench where the slab on grade is cast right over the footing, it is similar.
Dirt formed footing for a stem wall, with or without a basement. It seemed tricky (if even possible) to support stem wall forms over FB ormless footings. I wondered the additional cost of 2 pours over 1, might be offset by not forming for footing.

Actually, around here, it's either monolithic thickened edge slab with foam for SFPF, or ICFs if a basement. Some Superior Wall foundations for basements.

My unheated solo build garage is all block foundation.
 
Looking further at this, it seems to be mostly crawl space houses, not fulk basements. One article showed supporting stem wall forms on 1x2 (article text - looked more like 1x3 or 1x4 in photos) and pulling them at end of day one, leaving stem wall forms sitting on 8 hour cured unformed footings. In Califorina of course.

Underlying this was GC doing it without hiring a sub.
 
I had interesting feedback from a contractor today about a job. He told me that the GC want them to use grade beams instead of a footing and stem wall because the grade beams were cheaper? Not sure how that works because the grade beams are 24" wide and 36" tall.
 
More concrete but less formwork and can reduce the time from digging the footing and pouring concrete.. This is typical when there is no crawl space and a slab on grade is used
 
A different view might suggest designs using less concrete because of the environmental consequences. From a recent article "Concrete is the world's most widely consumed material after water, and its production contributes to more than 7% of global CO2 emissions. "
 
And I'm only asking about what is required by the IRC, not what is often done, specifically seismically inactive areas. I am certain no reinforcing is required in the footing. Just trying to find if and where in the code and when dowels or a key is required between footing and stem wall. Any foundation on gravel footings, including wood and precast, of course is not required to be pinned. Just looking at poured and specifically block foundation prescriptive requirements.
What of frost heaving in NY?
 
Interesting. In thousands of foundation jobs here, only one was done monolithically and it was a complete disaster. The guy was an engineer from Israel and had no clue about construction in our climate. We had to explain that the foundation needed to be below frost to him. I would like to see a professional do it.

I have not heard of an epidemic of leaks in 2 pour method.
I hear a belief that engineers do not know what they are doing. For those individuals I recommend that they not enter any building designed by an engineer. This includes hospitals, public buildings, most commercial buildings, and any building taller than a few stories.

For the record there are many residential footings cast monolithically that have not had problems. Could the problems have been related to the competency of the contractor?
 
I hear a belief that engineers do not know what they are doing. For those individuals I recommend that they not enter any building designed by an engineer. This includes hospitals, public buildings, most commercial buildings, and any building taller than a few stories.

For the record there are many residential footings cast monolithically that have not had problems. Could the problems have been related to the competency of the contractor?
Oh, absolutely. The contractor was definitely the issue. Although, he was the same person as the engineer. Contractor and engineer all in one.

I wouldn't say that engineers don't know what they are doing. I do believe that this one was operating outside of his competency.

I would certainly agree with you that the one that I saw and had major issues with leaks is certainly not a proper sample size to develop a fully formed position on it. However, I feel the other conclusion is fairly solid; that there really is not much risk in a foundation leaking simply because it is a two pour system.
 
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